Here are some options:
For storing at bedside or in the headboard, an Uncle Mike's cheapo soft IWB holster (I use a #7) fits snugly, wrapping around the trigger guard in back. It's not so great for carrying but sometimes you just want something to cover the gun and trigger when you're not wearing it.
A basic belly-band, 4" wide fits the XD-M line very well and is one of my in-house carries when I'm just wearing sweats.
A 5.11 holster shirt is very good if you have a 42"+ chest - it holds the HG very securely vertically in just the right place under the armpit. Very comfortable.
A Fobus basic paddle holster, OWB fits well, but it doesn't hold the HG very close to the body. Model number is SP11B. Another cheap holster which is just OK.
The best kind is a Raven (Raven Concealment Systems), but there's a multi-month waiting list. It's IWB, kydex around $80. Check the Crossbreed Supertuck and the Minotaur MTAC. All are IWB.